Are LED bulbs heat sensitive. The specific reason I am asking is that there is just one bulb in the kitchen, in the middle of the ceiling with a globe. I always use a 100W bulb and it is always burning out. There are two obvious reasons for this and I am fairly certain they both contribute: the kitchen light is on a lot and being behind a globe on the ceiling makes it hard to dissipate heat. The bulb is also a real nuisance to replace since I have to get a ladder and then get the globe seated with three set screws in an awkward arms over my head position.
I began to think that the next time I replace it, I would get an LED bulb. I did buy one (it was quite expensive, over $30) and am, for the time being, using it in my bed lamp, where I also need 100W equivalent light. The bulb is 19W and really bright. But it clearly will generate a fifth as much heat as an incandescent and I began to wonder if that would shorten its life so as to defeat my purpose, which is not so much to save electricity cost as it is to avoid having to replace the bulb every year or so.
Yes, they are heat sensitive.
If this lamp is burned base-up, in an enclosed fixture, it might well overheat the electronics. Are there any openings in the fixture to allow hot air to escape?
Yeah, heat sensitivity is a real issue with LED’s. They don’t make much heat, as you noted, a fifth of what the incandescent bulb does, but they don’t tolerate heat as well as a glass and metal bulb, being made of mainly plastic. Some have big old aluminum heat sinks that help with that, though. That’ll make it hard to fit into a recessed fixture.
I use a lot of LED lights. They are heat sensitive, although it’s mitigated by the fact that they generate a lot less heat then equivalent incandescent or fluorescent lights. I wouldn’t put one in a totally sealed enclosure if it’s on for any significant length of time. Which a primary kitchen light would be.
You have multiple options, I think:
Don’t put the enclosure back on. Sometimes function is more important than style.
Don’t put the enclosure all the way back on. Can you leave a gap of a cm or so without risking it falling down?
Cut some holes into ceiling that’ll be hidden by the enclosure. Two or three holes that’ll allow heat to flow into the space might be enough. Your judgement on whether it’s workable. And find out where the wires are before you cut!
Your 100w incandescent bulb is putting out about 90w of heat. Your LED bulb uses that much less energy primarily because it isn’t wasting 90% of it’s energy putting out heat.
All the points about the wondrous advantages of LEDs are perhaps spot-on, as far as I have been reading about them. (But I haven’t had occasion yet to try one myself. Are they coming down into a reasonable price range yet?)
But the most direct and immediate response to the OP is: Get rid of the f’ing globe fixture and replace it with something else.
Those globe fixtures are a PITA for the reasons the OP states. They are a PITA to remove and replace (the one in my dining area, having been once dismounted [by me], remains dismounted to this day), and I do worry about the amount of hot air they retain. (Is there any reason why this is good? Does it help old-fashioned incandescent bulb life to be kept in a hot ambient environment?)
Someday, if you should happen to do this, take a look at the wires in the ceiling just behind the fixture baseplate, and notice how cooked they are. You will find the insulation to be dry and brittle and perhaps already cracked and flaking off. :eek: Your home might just as well be invaded and burnt to the ground by fire ants.
This big issue is how…
Turns out that incandescent lamps radiate most of their heat away. So, even though they are abysmally inefficient, the heat ends up across the room, or on the chair you are sitting in. LEDs don’t have that luxury. The waste heat they generate is at a much lower temperature, so it has to be conducted or convected away, which has been one of the biggest engineering challenges to their economical manufacture.
Nothing would please me more than getting rid of that globe, but a bare bulb would make my wife freak. Maybe I can replace the fixture. It is certainly worth a try.
Incidentally, while that 19W bulb is hot, you can touch it without pulling off immediately. And it is really bright. Maybe I could get a fixture with room for two 60W equivalent bulbs.
The globe on LED lamps will run fairly cool - it’s the electronics that generate much of the heat, and are the most heat sensitive. Touch the heatsink, and see how warm it is.